An architect built a perfectly circular summer home on an island for his family in 1971. Now, it's on the market for $1.9 million check it out.

The islands are in Lake Huron's Georgian Bay. The house, also known as Table Rock Cottage, sits on the biggest island of the collection.

Canadian architect William Grierson built Table Rock Cottage in 1971 as a summer retreat for his family, per the listing.

"The island is accessible only by boat. As children, my brother and I spent entire summers there and family friends would come to stay," Sarah Waterfield, the current owner and Grierson's daughter, told Insider.

George Webster with Royal LePage Meadowtowne Realty holds the listing.

One of those islands is a one-acre rock island known as "Moby Dick." The other five islands range between a half-acre and one acre in size, per the listing.

Houses in Georgian Bay have an average house price of CAD $1.2 million, per data from Canadian real-estate platform Zolo.com.

Currently, 12 private islands in Georgian Bay are for sale, with prices ranging from CAD $3.5 million to CAD $1.1 million, per real-estate platform Private Islands Inc, which is dedicated to island properties. The Table Rock Islands package is in the mid-price range.

The islands were uninhabited when Grierson bought them in 1965, according to an excerpt from a book about Grierson's career that Waterfield sent to Insider. Titled "William Grierson: Selected Works," it was written by Grierson's wife, Joan, together with writer Alex Champlin.

The only sign that anyone else had ever been on the island before Grierson was a brass plaque left behind by the Hydrographic Services of Canada as a record of their visit in 1961, per the book.

The house's wide, sloping roof is held up by 24 concrete columns placed along the exterior perimeter of the house, per the book. At the core of each column is a metal rod that's embedded into the ground to ensure that the building can withstand storms.

"Even on rainy days, there is a wonderful sense of ease and we gather by the fire to play board games and drink tea," Waterfield said.

Waterfield and her brother spent lots of time playing in the waves — fishing, snorkeling, and even sailing.

"Back then, summer time seemed endless," Waterfield said. "It is a very special place and has its own rhythm, as islands do."

The island is remote, but Waterfield said there was plenty to do every summer when they were there.

"Far from idle, we were always busy working on the next project — whether it was building a new dock, building a boathouse, or even painting dining chairs," Waterfield added.

Table Rock Cottage was powered by an oil generator when it was first constructed. Grierson installed solar panels in the 1980s, per the book.

"The building allows for many people, so everyone has their own space and it never feels crowded," Waterfield said.

For the water and plumbing system, Grierson had to blast open the rock bed on the island and create a trench where he could place the pipes, per the book.

When the house was built, Grierson had floating docks installed, per the book. However, they were often damaged by strong winds and heavy rain, which caused them to detach and float out into the open water.

"The site is spectacular, with extraordinary sunsets, shooting stars, and August moons. There is no other place like it on earth," Waterfield said.

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